David Rosenthal

No mental phenomenon is more central than consciousness to an adequate understanding of the mind. Nor does any mental phenomenon seem more stubbornly to resist theoretical treatment. Consciousness is so basic to the way we think about the mind that it can be tempting to suppose that no mental states exist that are not conscious states. Indeed, it may even seem mysterious what sort of thing a mental state might be if it is not a conscious state. On this way of looking at things, if any mental states do lack consciousness, they are exceptional cases that call for special explanation or qualification. Perhaps dispositional or cognitive states exist that are not conscious, but nonetheless count as mental states

According to Dennett, the facts about consciousness are wholly fixed by the effects consciousness has on other things. But if a mental state's being conscious consists in one's having a higher-order thought about that state, we will in principle have an independent way to fix those facts. Dennett also holds that our speech acts sometimes determine what our thoughts are, since speech acts often outrun in content the thoughts they express.I argue that what thoughts we have is independent of how we express them in speech, and that this is consonant with speech acts’ often seeming to have more fine grained content than the thoughts they express. This model has the advantage, compared with Dennett’s, of accommodating our folk-psychological taxonomy of intentional states and preserving the traditional idea that speech acts express antecedent intentional states. Speech acts doubtless do sometimes have richer content than the thoughts they express, though sometimes verbally expressing a thought simply makes us conscious in a more fine-grained way of what that content is.On the higher-order-thought model, as on Dennett’s, a mental state’s being conscious is, in effect, our spontaneously interpreting ourselves as being in that state. But such spontaneous self-interpretation need not be the last word on what content our thoughts have. Even though the content of speech acts sometimes outrun that of the thoughts they express, we can explain why the two seem always to be exactly the same. Even when a speech act is richer in content than the thought it expresses, the well-entrenched pragmatic equivalence between saying something and saying that one thinks that thing ensures that one will be conscious of one’s thought as having the richer content of the speech act that expresses it. We are conscious of our thoughts as having the content that our speech acts would capture.

In Descartes's time the issue between materialists and their opponents was framed in terms of substances. Materialists such as Thomas Hobbes and Pierre Gassendi maintained that people are physical systems with abilities that no other physical systems have; people, therefore, are special kinds of physical substance. Descartes's DUALISM, by contrast, claimed that people consist of two distinct substances that interact causally: a physical body and a nonphysical, unextended substance. The traditional

Conscious mental states are states we are in some way aware of. I compare higher-order theories of consciousness, which explain consciousness by appeal to such higher-order awareness (HOA), and first-order theories, which do not, and I argue that higher-order theories have substantial explanatory advantages. The higher-order nature of our awareness of our conscious states suggests an analogy with the metacognition that figures in the regulation of psychological processes and behaviour. I argue that, although both consciousness and metacognition involve higher-order psychological states, they have little more in common. One thing they do share is the possibility of misrepresentation; just as metacognitive processing can misrepresent one’s cognitive states and abilities, so the HOA in virtue of which one’s mental states are conscious can, and sometimes does, misdescribe those states. A striking difference between the two, however, has to do with utility for psychological processing. Metacognition has considerable benefit for psychological processing; in contrast, it is unlikely that there is much, if any, utility to mental states’ being conscious over and above the utility those states have when they are not conscious.

Dualism is the view that mental phenomena are, in some respect, nonphysical. The best-known version is due to Descartes, and holds that the mind is a nonphysical substance. Descartes argued that, because minds have no spatial properties and physical reality is essentially extended in space, minds are wholly nonphysical. Every human being is accordingly a composite of two objects: a physical body, and a nonphysical object that is that human being's mind. On a weaker version of dualism, which contemporary thinkers find more acceptable, human beings are physical substances but have mental properties, and those properties aren't physical. This view is known as property dualism, or the dual-aspect theory

It’s often held that undetectable inversion of mental qualities is, if not possible, at least conceivable. It’s thought to be conceivable that the mental quality your visual states exhibit when you see something red in standard conditions is literally of the same type as the mental quality my visual states exhibit when I see something green in such circumstances. It’s thought, moreover, to be conceivable that such inversion of mental qualities could be wholly undetectable by any third-person means. And since first- person access is limited to a single individual, and so could not reveal a disparity in mental quality between us, third-person undetectability means undetectability tout court

At the level of our platitudinous background knowledge about things, speech is the expression of thought. And understanding what such expressing involves is central to understanding the relation between thinking and speaking. Part of what it is for a speech act to express a mental state is that the speech act accurately captures the mental state and can convey to others what mental state it is. And for this to occur, the speech act at least must have propositional content that somehow reflects that of the mental state, and perhaps must have other such properties as well.